Electronic Motor

I am looking to buy a motor suitable to operate a shake table in a school setting, to create an earthquake.
I talked to different people and were given different advise, stepper motor DC motor or something similar. On the pics below you can see the table,it has a shaft go through the table which is about 7mm diameter and currently 80mm long. Happy to use a coupler to attach motor to current shaft.
Any idea on what motor and extra equipment I need to buy/use to do this project.
Thanks all

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Hi Caroline,

What’s approximately the torque that would be required in order to turn the shaft? With an appropriate adapter, something simple such as this worm gear motor could be suitable depending on your requirements.

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HI Bryce,
Thanks for replying, I am not too sure what torque I need. I do know that the motor needs to be able to turn the ‘table’ at different speeds. What I mean by that is a low, medium and faster shaking motion and I need to be able to control it. E.g. 30 sec on each of the different speed settings.
Thanks so much

Hi Caroline
With the information provided I doubt anyone could recommend any specific motor. In a nutshell I think what you need is a speed controllable motor that is large enough to drive this table.
What are you going to put on this table. This will have a bearing on the motor size as the load will change.
How are you going to mount it. Different motors have many different mounting methods.
What is your proposed power source. Battery, 240VAC or other. This will be a factor in deciding what type of motor and speed controller.
Do you have any motor/speed controller on hand or do you have to purchase.
Yes you could use a stepper but you still have to drive it and control the speed, mount it etc.
I would assume the view showing the pulleys and belt is the under side of this unit and the motor attaches to the smaller of the pulleys. I also assume the part attached to the glass (??) plate is eccentric and moves the plate around as it rotates. If the load is not too great and depending on the maximum speed required a quite modest geared hobby motor of the larger variety may well do the job. But if unsure going larger is better than having smoke.
As a matter of interest a fitter friend of mine need a shaker table for a specific task so he made one. Square steel plate about 75 x 75 cm mounted on springs. Underneath he bolted a motor he had on hand and connected via a speed controller. He then fitted a pulley to the motor shaft with an adjustable weight at one point. This created an out of balance situation and in operation the plate shook like crazy. The amount of shake determined by the position of this weight and the frequency by the motor speed. Worked very well but the motor bearing failed after a few years with the sideways load caused by the imbalance.
Cheers and good luck. Bob R

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Hi Caroline
A follow on.
Just had a thought. As an experiment you could try using a variable speed electric drill attached to that 7mm shaft. Battery or 240VAC.
This may give you a better idea of what will be required. If you have to use a higher wattage drill to operate the table in a satisfactory manner you will ned a larger motor.
If the table is only to be used infrequently the drill idea may be a simple way out of your problem.
Cheers Bob R

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